During data communication, an active board is protected by a standby board. When an application fails in the active board, the standby board should be able to detect the error quickly and take over the routing service seamlessly.
In the prior art, the method for packet backup is an explicit real-time backup. In other words, the interface board only sends a peer packet to the active board, and the active board backs up all the processing results to the standby board in real time after processing the peer packet.
However, because an explicit real-time backup is used in the prior art, in particular, the active board needs to receive a packet, process the packet, back up the packet to the standby board and send the packet, thus the burden of the active board is too heavy, and in the case of heavy load, the communication between the processes may be unreliable. Moreover, all the data processed by the active board have to be backed up to the standby board via the transport layer. Therefore, the load of the communication channel between processes may be too heavy.
To implement an implicit backup, the other method for packet backup in the prior art is as follows:
An interface board sends a peer packet to the standby board;
The packet is duplicated to the active board;
The active board processes the packet and feeds back the processing result to the standby board; and
The standby board backs up and sends the result.
In this solution, the load of the active board may be reduced and the communication reliability may be improved. However, although the packet is received and sent by the standby board, the active board still needs to duplicate a large volume of data to the standby board, which causes an excessive load of the communication channel and deteriorates the communication.